package com.hzsparrow.framework.utils;

import org.apache.commons.lang3.StringUtils;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**
 * 敏感词过滤
 */
public class SensitivewordFilterUtils {

    @SuppressWarnings("rawtypes")
    private Map sensitiveWordMap = null;

    public static int minMatchTYpe = 1; //最小匹配规则

    public static int maxMatchType = 2; //最大匹配规则

    /**
     * 字符串形式初始化敏感词库
     *
     * @param keyWordStr 敏感词字符串集
     * @param separator  切分字符
     */
    public SensitivewordFilterUtils(String keyWordStr, String separator) {
        sensitiveWordMap = new SensitiveWordInit().initKeyWord(keyWordStr, separator);
    }

    /**
     * 读取文件形式初始化敏感词库，每行一个敏感词
     *
     * @param filePath 文件路径
     */
    public SensitivewordFilterUtils(String filePath) {
        sensitiveWordMap = new SensitiveWordInit().initKeyWordByFlie(filePath);
    }

    /**
     * 判断文字是否包含敏感字符
     *
     * @param txt       文字
     * @param matchType 匹配规则&nbsp;1：最小匹配规则，2：最大匹配规则
     * @return 若包含返回true，否则返回false
     */
    public boolean isContaintSensitiveWord(String txt, int matchType) {
        boolean flag = false;
        for (int i = 0; i < txt.length(); i++) {
            int matchFlag = this.checkSensitiveWord(txt, i, matchType); //判断是否包含敏感字符
            if (matchFlag > 0) { //大于0存在，返回true
                flag = true;
            }
        }
        return flag;
    }

    /**
     * 获取文字中的敏感词
     *
     * @param txt       文字
     * @param matchType 匹配规则&nbsp;1：最小匹配规则，2：最大匹配规则
     * @return 敏感词集
     */
    public Set<String> getSensitiveWord(String txt, int matchType) {
        Set<String> sensitiveWordList = new HashSet<String>();

        for (int i = 0; i < txt.length(); i++) {
            int length = checkSensitiveWord(txt, i, matchType); //判断是否包含敏感字符
            if (length > 0) { //存在,加入list中
                sensitiveWordList.add(txt.substring(i, i + length));
                i = i + length - 1; //减1的原因，是因为for会自增
            }
        }

        return sensitiveWordList;
    }

    /**
     * 替换敏感字字符
     *
     * @param txt       文字
     * @param matchType 匹配规则&nbsp;1：最小匹配规则，2：最大匹配规则
     * @return 替换后的字符串
     */
    public String replaceSensitiveWord(String txt, int matchType) {
        return replaceSensitiveWord(txt, matchType, "*");
    }

    /**
     * 替换敏感字字符
     *
     * @param txt         源字符串
     * @param matchType   匹配规则&nbsp;1：最小匹配规则，2：最大匹配规则
     * @param replaceChar 替换字符，默认*
     * @return 替换后的字符串
     */
    public String replaceSensitiveWord(String txt, int matchType, String replaceChar) {
        String resultTxt = txt;
        Set<String> set = getSensitiveWord(txt, matchType); //获取所有的敏感词
        Iterator<String> iterator = set.iterator();
        String word = null;
        String replaceString = null;
        while (iterator.hasNext()) {
            word = iterator.next();
            replaceString = getReplaceChars(replaceChar, word.length());
            resultTxt = resultTxt.replaceAll(word, replaceString);
        }

        return resultTxt;
    }

    /**
     * 获取替换字符串
     *
     * @param replaceChar 字符
     * @param length      长度
     * @return 指定长度的字符
     */
    private String getReplaceChars(String replaceChar, int length) {
        if (StringUtils.isBlank(replaceChar)) {
            replaceChar = "*";
        }
        String resultReplace = replaceChar;
        for (int i = 1; i < length; i++) {
            resultReplace += replaceChar;
        }

        return resultReplace;
    }

    /**
     * 检查文字中是否包含敏感字符
     *
     * @param txt        源字符
     * @param beginIndex 开始下标
     * @param matchType  匹配标识数，匹配一次加1
     * @return 如果存在，则返回敏感词字符的频次，不存在返回0
     */
    @SuppressWarnings({"rawtypes"})
    public int checkSensitiveWord(String txt, int beginIndex, int matchType) {
        boolean flag = false; //敏感词结束标识位：用于敏感词只有1位的情况
        int matchFlag = 0; //匹配标识数默认为0
        char word = 0;
        Map nowMap = sensitiveWordMap;
        for (int i = beginIndex; i < txt.length(); i++) {
            word = txt.charAt(i);
            nowMap = (Map) nowMap.get(word); //获取指定key
            if (nowMap != null) { //存在，则判断是否为最后一个
                matchFlag++; //找到相应key，匹配标识+1 
                if ("1".equals(nowMap.get("isEnd"))) { //如果为最后一个匹配规则,结束循环，返回匹配标识数
                    flag = true; //结束标志位为true   
                    if (SensitivewordFilterUtils.minMatchTYpe == matchType) { //最小规则，直接返回,最大规则还需继续查找
                        break;
                    }
                }
            } else { //不存在，直接返回
                break;
            }
        }
        if (matchFlag < 2 || !flag) { //长度必须大于等于1，为词 
            matchFlag = 0;
        }
        return matchFlag;
    }

}
